184; LIFE OF surface of the moon, it will be comprehended what important laws of terrestrial organisation cim be de- duced and revealed by contemporary and comparative observations over such a large field. The Kunsian government at once acknowledged the importance of these plans, and instituted a physical observatory in St. Petersburg, whose task it was to choose the other observatory stations, to compare and adjust the instru- ments with which the experiments were to bo made,—• accurately to determine the astronomical position rof the stations selected, to superintend and direct the magnetic and meteorologic researches, to arrange the collected results, to calculate them, and to publish the mean results. The special mhieralogic geognostic experiences and inquiries which had resulted from the Asiatic expe- dition, were confided to the care of Gustav Rose, one of Humboldt's companions. His work appeared in two volumes in the years 1837 and 1842, as a portion of the collective work,* under the special title <fi JMino- ralogicai geognostic division and historical account of the journey," and Humboldt had given the com- piler a large number of notes and observations from his own diary. But before the third part of the col- lective work appeared, which was to contain the botanic and zoological results arranged by Ehrenberg, and the investigation into the geographic distribution of plants and animals/Humboldt published another new work under the title : " Asie centrale, rechorehes sur les chaines des montagnes et la climatologie eom- paree/' (Paris, 1843, in three volume^) which was soon afterwards enlarged and translated into German, by W* Mahlmann. This work is the real result of the studies, which Humboldt had for many years devoted to this subject. We have mentioned in former chapters, when he first * The collective title runs thus; "Expedition to the Ural, tlia Altai, and the Gaspian seas by command of his majesty tlxe Bmporor of Russia, in the year 1820, made by Alexander -von Humboldt, G* Ehrenberg1, and Gustav Rose*"